The toxic fraction of gliadin digests in coeliac disease. Isolation by chromatography on Biogel P-10.
Improvement in the fractionation of gliadin digests and in the isolation of toxic fractions was achieved using chromatography on Biogel P-10. Fraction V, one of the 11 fractions eluted from a peptic-tryptic digest of crude gliadin extracted from Cappelle wheat, significantly affected coeliac jejunal mucosa in organ culture. BV, gamma V, omega V, the corresponding fractions V from beta-, gamma- and omega-gliadins, displayed similar toxic effects. Fraction VI containing peptides with a lower molecular mass did not show any significant cytotoxic activity and, moreover, inhibited the toxicity of fraction V. Analysis of the toxic fractions V showed that they contained peptides of 7-8,000 molecular mass, rich in proline and glutamine and poor in aromatic amino acids and carbohydrates. Among the various fractions, V, beta V from beta-gliadin appeared the less heterogeneous.
D000596:Amino Acids / Q000032:analysis; D002446:Celiac Disease / Q000175:diagnosis*; D002648:Child; D002850:Chromatography, Gel / Q000379:methods; D046508:Culture Techniques; D005903:Gliadin / Q000032:analysis* / Q000302:isolation & purification / Q000633:toxicity; D006801:Humans; D006868:Hydrolysis; D010434:Pepsin A; D010940:Plant Proteins / Q000032:analysis*; D014357:Trypsin
D000596:Amino Acids; D010940:Plant Proteins; D005903:Gliadin; D014357:Trypsin; D010434:Pepsin A